William Pack’s life story is testament to what hard work and sheer willpower can do to change one’s future.

Born right outside of Roundup, Mont., Pack lived in what he calls “abject poverty.” He recounts his adolescent years in a matter-of-fact kind of way, almost as if they had happened to someone else — or most likely in Pack’s case, as if someone would if they had been through those moments over and over in their head.

He talks about his family’s Sunday baths, where each member, one by one, would take a seat in a tub in the middle of their kitchen.

“You didn’t want to be the fourth person taking a bath because the water wasn’t thrown out, it was reused,” he says.

He remembers the family having to shoot or catch their meals and recalls his first job at age 12. Addiction and abuse surrounded him until at 15 years old, he finally walked away from his family and was emancipated by the courts. And at 16 he was a high school dropout.

For the next six years he held down a plethora of jobs. It wasn’t because he couldn’t keep one, he says, but because no one else was going to pay his rent, or his bills.

He was a dock worker, bartender and truck driver. He drove a Zamboni for a local hockey team and was a night auditor for a Holiday Inn, a job for which he had no experience and had to lie about his age to get.

But as he tells his story, he pauses every few minutes to say that he didn’t have it so bad and that there are many others who grow up in much worse environments than he did. Pack even says that he’s happy he went through what he did because it helps him have a better perspective of where his life is now.

Pack, 52, is now a retired stockbroker turned author. His first novel, “The Bottom of the Sky,” is set to go on sale in June. Although a fictional story, the novel was “substantially” influenced by his life. The novel follows a brother and sister through their lives, starting in Roundup, Mont., and weaving through Wall Street, San Francisco and Silicon Valley. Pack says, however, that the characters’ trails and tribulations have come from his observations of life, not his experiences.

“Many people who I’m close to, or who know me, are going to be greatly surprised and in some instances shocked at the subject matter and the intensity level of the book,” he says.

The book is centered on the abuse of power, Pack says — of adults over children, men over women and the socially elite over the rank and file in the workplace.

Much of that abuse he says he saw as a stockbroker throughout his years at Merrill Lynch and later as the executive vice president and divisional director of Northern California for Citigroup Smith Barney.

He began his career at age 21 with Merrill Lynch and became the youngest office manager in the company four years later. He did all of this without a high school diploma. Because of his status with the company, many people just assumed he had an education.

But Pack’s life changed at 41 when he fell severely ill. While home he took a look at his life and decided he needed to do something different.

“I decided it was time to do something I wanted to do with my life instead of being trapped in something I did originally just to get out of poverty,” he says.

So he quit his job on Wall Street, took the SAT exam and was accepted into Stanford University, where he was the oldest undergraduate at the time.

While at Stanford, Pack met John L’Hereux, a novelist and contributing editor for The Atlantic Monthly. L’Hereux had read some of Pack’s short stories and said that he should think about writing a novel. L’Hereux even promised to edit the book.

Not wanting to pass up the opportunity, Pack took L’Hereux up on his offer and began writing The Bottom of the Sky. And after years of work and countless hours of writing, the novel is on the eve of being published.

“Writing fiction is much, much more difficult than I anticipated it would be,” Pack says. “I had to have a lot more isolation. You really have to cave within yourself to write authentically.” The writing process, he says, was difficult, but also extremely rewarding.

“When I sat down to write the book, I did not know the characters. I did not yet know the tale,” he says. “What occurs, if you stay with characters, the story, long enough, is you begin to know them as well as you know a real person in your life.” Though he knows that his life will be consumed with promoting the book, Pack says he can’t wait to sit down and begin the next one.